<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>大div中，三个小div水平居中</title>
    <style>
        *{
            margin:0;
            padding:0;
        }
        
    .small1,.small2,.small3{
        width: 200px;
        height: 200px;
        line-height: 200px;
        margin: 0;
        padding: 0;
        display: inline-block;
        _display: inline;
        *display: inline;
        zoom: 1;
        background: beige;
    }
    </style>
</head>
<body>
    <div class="big_div">
        <div class="small1">
            小div1
        </div>
        <div class="small2">
            小div2
        </div>
        <div class="small3">
            小div3
        </div>
        <div style="clear:both"></div>
    </div>
</body>
</html>